Short answer: No

Personally, I use fenders. They're practical where I live commuting 5 days a week in all weather. They help keep you and your drivetrain clean. I commuted an entire year and it just became annoying to clean up my bike and get all the grit and grime out of components (and my face). Its far less these days and probably wont take them off my commuter.

You dont NEED fenders, but they make my life easier. My guess is it wasn't sealed properly.